Babies cry a lot because it is their only way to communicate, and their immature nervous systems make them prone to becoming overwhelmed by ordinary experiences like hunger, fatigue, and sensory input. Crying typically peaks between 6 and 8 weeks of age, averaging 2 to 3 hours per day for a healthy infant. Some babies cry considerably more. The good news: most of this crying is a normal developmental phase that tapers off significantly by 3 to 5 months.
The Normal Crying Peak
Newborns don’t cry much in their first week or two, which can make the sudden increase around weeks 3 to 6 feel alarming. Crying ramps up through the first month, hits its highest point around the second month of life, then gradually decreases by the end of the fifth month. This pattern is so universal across cultures that pediatric researchers gave it a name: the Period of PURPLE Crying, where each letter describes a feature of this phase.
The “P” stands for peak of crying, reflecting that predictable rise and fall. “U” is for unexpected: your baby may cry on and off for no apparent reason. “R” means resists soothing, because sometimes nothing you try will work. The second “P” stands for pain-like face, meaning your baby may look like they’re hurting even when nothing is wrong. “L” is for long-lasting, since some babies in this phase cry for five hours a day or longer. And “E” is for evening, because late afternoon and evening crying is especially common.
Understanding this pattern matters because it reframes what feels like a problem into something expected. Your baby isn’t crying five hours a day because you’re doing something wrong. Their nervous system is still developing the ability to cope with everyday stresses, and crying is the only tool they have. As their nervous system matures and they gain greater bodily control, they become better at consoling themselves and experience fewer frustrations.
What Babies Are Trying to Tell You
Even though much of infant crying has no identifiable cause, some of it does. Learning to catch these signals early can reduce the total amount of crying you deal with each day.
Hunger is the most common trigger, but crying is actually a late sign of hunger. Before a baby cries from hunger, they’ll put their hands to their mouth, turn their head toward your breast or a bottle (called rooting), smack or lick their lips, or clench their fists. Catching these cues and feeding before the crying starts keeps the baby calmer and makes feeding easier, since a frantically crying baby has a harder time latching.
Overstimulation is another major cause, and it looks different from hunger. Babies become overwhelmed when they’re tired, have been passed around to several people, are off their routine, or are simply not feeling well. An overstimulated baby will look away as if upset, make jerky movements, clench their fists, wave their arms and legs, and become increasingly difficult to distract or please. The fix is the opposite of what many caregivers instinctively try: instead of more bouncing, more noise, or more eye contact, the baby needs less. A dim, quiet room with minimal handling often works better.
Discomfort rounds out the usual suspects: a wet diaper, being too hot or too cold, gas, or needing to be held. These tend to produce crying that stops once the problem is solved, unlike the developmental crying of the PURPLE period, which can persist no matter what you do.
When Crying Might Signal Colic
If your baby’s crying feels extreme compared to what other parents describe, colic may be the reason. The standard diagnostic criteria, known as the “rule of three,” defines colic as crying more than three hours per day, more than three days per week, for longer than three weeks. It affects an estimated 10% to 40% of infants worldwide.
Colic isn’t a disease. It’s a label for the far end of the normal crying spectrum, and no single cause has been identified. Colicky babies are otherwise healthy, gaining weight normally, and feeding well. The crying tends to follow the same developmental arc as regular infant crying, peaking around 6 to 8 weeks and resolving by 3 to 4 months. That timeline doesn’t make it easier to live through, but it does mean there’s a clear end point.
Reflux and Other Physical Causes
Most babies spit up. Normal spit-up is a gentle, easy flow of milk back through the mouth, and it doesn’t bother the baby. Reflux becomes a concern when spit-up comes out with force (shooting rather than oozing), the baby cries more than usual or seems consistently irritable, or feeding becomes a struggle. If your baby arches their back during or after feeds, refuses to eat, or isn’t gaining weight, those are signs the reflux may be painful rather than just messy.
Other physical causes of persistent crying include ear infections, food sensitivities (especially to cow’s milk protein in formula or the breastfeeding parent’s diet), constipation, and skin irritation. These tend to produce crying that’s different from the baby’s baseline: more sudden in onset, higher pitched, or accompanied by other symptoms like fever, rash, or changes in stool.
Signs That Need Medical Attention
Most infant crying is normal, but certain symptoms alongside the crying warrant a call to your pediatrician or a trip to urgent care.
- Fever in a baby under 3 months: Any fever at all in this age group needs a call to your doctor, regardless of how the baby seems otherwise.
- Fever in older babies: For babies 3 to 6 months, a temperature above 100.4°F (38°C) or any fever with signs of illness. For 6 to 24 months, a temperature above 100.4°F lasting more than one day.
- Unusual sleepiness: A baby who is sleeping more than normal, hard to wake, or seems floppy.
- Refusing to eat: Missing two or more feedings in a row or eating poorly.
- Dehydration signs: Fewer wet diapers, crying without tears, dry mouth, or a sunken soft spot on the head.
- Vomiting after feedings or not keeping liquids down for eight hours.
- Breathing trouble: Fast or hard breathing, especially with a cough or signs of a cold.
- A rash that appears quickly, blisters, or looks infected, particularly with a fever.
If none of these apply but the crying still feels wrong to you, trust that instinct. You know your baby’s normal patterns better than anyone.
Keeping Yourself Safe When Nothing Works
There will be times when you’ve fed, changed, burped, rocked, and shushed your baby and they’re still screaming. This is the hardest part of early parenting, and it’s the moment when frustration can become dangerous. Shaking, throwing, hitting, or slamming a baby can cause permanent brain damage or death, and it happens most often when an exhausted caregiver reaches a breaking point during inconsolable crying.
If you feel your frustration rising to a point where you might lose control, put your baby down in a safe place like a crib or playpen (no blankets or stuffed animals), leave the room, and let them cry alone for 10 to 15 minutes. Your baby will not be harmed by crying in a safe space. Use that time to take deep breaths, listen to music, call a friend or family member, or do something simple with your hands like washing dishes. If you haven’t calmed down after 10 to 15 minutes, check on your baby but don’t pick them up until you feel steady. Then try soothing again.
This isn’t a failure. It’s the recommended safety protocol from the American Academy of Pediatrics, and it exists because even loving, devoted parents can reach a limit. Having a plan for that moment before it arrives is one of the most important things you can do in those early months.